The Scientific Method
by Spoofmaster
Summary: Martha Jones discovers one of the Doctor's less sanitary habits.
1. Queries

"What is it?" asked Martha, looking at the thing the Doctor held in his hand. It looked something like a teapot with a few too many protuberances and an unhealthy penchant for lime green paint, but the sonic screwdriver had identified it as the source of the interference that had been preventing the nearby human colony from communicating via anything more complicated than a semaphore tower. The inhabitants had been entirely cut off from the ships that hung in orbit around the odd little planet the Doctor and Martha had found themselves on after the TARDIS refused once again to take directions from her pilot, to devastating effect.

That and the fact that it had been humming in a vaguely upsetting manner since the Doctor had removed it from its little alcove in the cave wall (to which it was still attached by a number of thick tubes) made Martha reasonably sure that any resemblance it held to a kitchen appliance was only skin deep.

"I'm not sure," breathed the Doctor, putting on his glasses. He turned the possessed teapot this way and that, scrutinizing it.

"So in other words, you have no idea," smirked Martha, hands on hips. "Some savior of the galaxy you are. Can't even identify a space teapot." 

"Teapot?" The Doctor looked blankly at her for a moment before looking back at the object in question. He stared at it for several long moments, before a grin spread slowly across his face. "It does look like a teapot, doesn't it? Mind you, it'd take a human to make the connection. Never did meet another species quite so fascinated with boiling dried vegetable matter and drinking the result. Still, though, I can't say I don't appreciate a nice cuppa myself every now and then. Works wonders for the synapses, and you never know when you'll find yourself in need of a quick jolt to the brain. One time—"

"_Concentrate_, Doctor," said Martha. "The people in that colony are depending on us to get them back in touch with their ships."

"Ah. Yes. Mustn't forget what we came here for." The Doctor glared at the thing, willing it to divulge its secrets. Sadly, it did not.

He shrugged, and licked it.

"Oh," he said, as Martha stared, her mouth moving but no sound coming out. "Nithilian organic plastic. You can tell by the hexachlorophene they put on the outside to keep bacteria from getting into it—"

"I'm sorry, but did you just _lick_ that?" asked Martha incredulously, having finally regained the ability to speak.

The Doctor looked up from the alien artifact and into the disbelieving face of his companion, his eyes wide and innocent. "I suppose so," he replied, clearly not comprehending Martha's objection to his employment of the scientific method. "Why?"

"You don't know where that's been!" exclaimed Martha, trying not to lose her cool. The words 'I sound like my mum!' flitted through her head, and she clamped her mind down on them, willing herself not to follow that train of thought. The fact that the Doctor was still staring at her in wide-eyed incomprehension really wasn't helping, and it was times like these that she had to work rather hard to remind herself of his age.

"Yes I do," he replied, gesturing to the alcove where he had found the object in question. "It was in this handy little alcove."

"Yeah, but where'd it come from before that?" demanded Martha.

"The Nithilians?" tried the Doctor. "They're notoriously cleanly people…."

"But you didn't know it was them until you'd already gone and licked it!" objected Martha. "And besides that, you have no idea how much bacteria it could have picked up since they left it there—"

"—The hexachlorophene takes care of that—"

"—Which, again, you didn't know until you'd already licked it. Have you even thought about how unlikely it is that your body will have natural protection against alien bacteria? Honestly, I don't know how it is we haven't both contracted some sort of horrible alien disease and died by now, with all the places you take me."

"Ah, well—"

"But at least I'm being careful about it. You, though—going off and licking things you find in caves! What are you, five?"

Martha finally noticed the grin that had been growing on the Doctor's face for the past few moments, and broke off her tirade just as he was threatening to commence chuckling at her. She glared at him.

"What?"

"Martha Jones," he grinned. "Always thinking."

"As opposed to randomly licking things, yes," she replied, testily. "What's so funny, then?"

"Well, for starters, you're right about the alien bacteria," admitted the Doctor. "If we were ordinary travelers, we would definitely have caught something or other by now. But we're not ordinary travelers, are we?"

"Are you saying that there's some sort of Time Lord technology protecting us?"

"Yep." The Doctor popped the p on the end of the word purposefully, feigning a pensive look for a moment before going back to the grin. "Just one of the many benefits of TARDIS travel. Good thought, though."

"You still shouldn't lick things," said Martha, unwilling to drop the argument. "You could still end up ingesting something that disagrees with you."

"I'll keep it in mind," he conceded, though in a tone that suggested he would do nothing of the sort. Martha sighed.

"So what's that…Nithinian plastic thing, anyway? You said you'd seen one before."

"Nithilian organic plastic, and yes, I've come across one of these before now." The Doctor pointed the sonic screwdriver at the base of one of the tubes that ran between the object and the cave wall, the blue light flickering for a moment before the tube came away with a sickeningly wet crunch. Martha winced.

"What does it do?"

The Doctor moved on to the next tube, chuckling. "It blocks transmissions."

"But why?"

"Because the Nithilians think it's funny," explained the Doctor, detaching the last of the tubes. "Their idea of a practical joke is to throw an entire colony into chaos. They don't mean any particular harm by it, but I think it's safe to say that most other species don't appreciate their brand of humor."

"Ah. So that's it, then?"

"Yeah. Now that we've disabled the transmitter, the colony's communications should be up and running again. We'll just drop this off with the governor, and then we can be on our merry way."

He tucked the defunct transmitter under one arm and proffered the other to Martha, who took it.

"So that's the big crisis?" she asked. "A practical joke? What's next, are we going to save the Earth from whoopee cushions?"

"You never know," grinned the Doctor.

Martha rolled her eyes and slapped him on the shoulder, which served only to fuel his amusement. 'You never know,' indeed!

Deep down, though, she was not entirely sure that he was joking.


	2. Consequences

Martha Jones looked up from the book on Gallifreyan anatomy with which she had absconded from the TARDIS library the previous afternoon as the teakettle across the kitchen from her began to whistle. She slid the Bhrugji thirty-quen note she had been using as a bookmark between the pages after a moment, taking one last look at the illustration she had been trying to decipher despite the TARDIS's continuing refusal to translate any of the Gallifreyan circle writing Martha had seen around the ship, before getting up and busying herself with the task of making tea.

She set the teapot and two mismatched mugs on a tray she had found in the study, buried under a pile of what were apparently letters that had disappeared the posts of at least twenty different civilizations. She dug the creamer in the shape of a cow out of the refrigerator, where it had been put after the last time it had been used rather than being emptied, and put it and the sugar on the tray as well, followed by a bottle of what the Doctor had told her was the Time Lord version of Advil. Advil itself was, she was told, out of the question. A thought struck her, and she filled a glass with ice cubes and put it by the creamer.

Preparations done, Martha took the tray and made her way down the hall to where she last remembered seeing the door to the Doctor's room. She'd been a little bit surprised to learn that he even had a bedroom, as she'd never observed him to require sleep. Even when they had been visiting Shakespeare, she had fallen asleep before observing whether he would do likewise, and woken to find him already up and telling her how lazy humans were, and how she was wasting her life by spending so much of it unconscious. She had thought for a while that he might just spend all his time waking, but now it appeared that he just slept less than she did, and arranged their schedules so that she'd be too busy sleeping herself to catch him going to bed or getting up.

She arrived at his door and knocked, shifting the tray awkwardly to one arm. A muffled rustling came from the room, and she gave the occupant a moment to finish whatever he was doing before pushing the door open and letting herself in.

The room, like many of the rooms the Doctor occupied in his spare time, was a mess. Several pinstriped suits hung over the backs of the two chairs in the room, looking as if they had been thrown there, and every horizontal surface was covered in a mixture of papers, books, and scientific equipment. A bag of jelly babies lay on the dresser, half its contents spilled out over what looked like brand-new framed daguerreotype of a man with a shaved head and unfortunate ears standing in front of the TARDIS. At least five pairs of Converse trainers were scattered around the room.

Against the far wall was the Doctor's bed, a king-sized affair normally covered with an overstuffed comforter with an irregular pattern of brown, green, and dull orange stripes. Today, however, the comforter had been pulled loose, leaving the bed in its somewhat more aesthetically pleasing plain brown sheets, as the Doctor huddled against the headboard, dressed in his jimjams and wrapped in the offensive comforter, a copy of _The Complete Idiot's Guide to Etiquette _laying open beside him. He raised an eyebrow at Martha as she entered, but didn't speak.

"I thought you might like some tea," she explained, clearing a space on the little table next to his bed by pushing the papers on it off onto the floor with the edge of the tray and setting down her burden. "You're not even really sick, you know. There's no need for you to sit around in here all day and mope about it."

The Doctor opened his mouth as if to respond, but thought better of it and shut it without saying anything. Martha smirked and poured herself a mug of tea, before putting some of the ice in the other mug and pouring tea over it.

"You can even have it iced," she went on, sitting down after clearing a chair with the same method she had used on the table. "It'll do you good."

She took a sip of her tea and watched him pluck two pills out of the bottle and wash them down with his iced tea. He winced as he drank, but still didn't say anything. Setting the mug back down, he made as if to pick his book back up, his eyes avoiding Martha.

"Poor Dokah," said Martha, purposefully mangling the word, a sly grin on her face. "I could have told you something like this would happen. Oh, wait—I _did_ tell you, and you went and licked the stupid thing anyway."

The Doctor glowered at her. "Marfa—"

He stopped, looking appalled at having allowed her to goad him into trying to talk to her while his speech was still garbled. Martha laughed.

"I don't mean to say 'I told you so,' but really…I did tell you so," she grinned. "I mean, you didn't even check to see what that device even felt like before you went and licked it, and look where it got you."

"Are you qui'e figishe'?" asked the Doctor irritably.

"'Oh, Marfa, I've hur' by 'ug!'" exclaimed Martha, doing her best impersonation of the Doctor.

The Doctor pointedly picked up his book and buried his nose in it, holding the tome in front of his face to block Martha's view of him. She giggled, and reached up to pull the book down.

"Let me look at it," she said, sobering. "I need to see if the swelling has gotten worse."

The Doctor rolled his eyes, but obediently stuck his tongue out for Martha to see. She leaned in, squinting at it and tutting softly, while he trained his eyes on the ceiling and did his best to pretend that she didn't have any right to rub the current state of affairs in.

"Well, at least the swelling has gone down," she finally said, leaning back and picking up her tea. "Still looks like you attacked it with sandpaper, though." She took a sip of her tea and thought about it. "That's probably about what you did, actually. I could have told you the thing was as rough as a nail file, but no, you just had to yank it out of my hands and lick it."

The Doctor harrumphed. "I was gust checkig 'o see wha' i' was bage of."

"Well, I hope you've learned your lesson," said Martha smugly. "No more licking things you find on strange planets, all right?"

"Baybe," replied the Doctor stubbornly, crossing his arms, giving Martha her turn to roll her eyes. He leveled his best glare at her, but she just laughed again and got up, brushing off her jeans before heading for the door.

"'If on'y I ha' listene' 'o Marfa!" she exclaimed, smirking at the Doctor from across the room.

"Va's egough," said the Time Lord, doing his best to sound intimidating despite the condition of his tongue.

"'Maaaaarfaaaaaaaaaaa!'" shouted Martha as she departed down the hall, unable to resist one last dig at the Doctor. She knew that she shouldn't make fun of him, but how often did one get to make jibes about a nine-hundred-year-old alien's self-inflicted injuries?

Sometimes, it just felt good to be right.


End file.
